During their investigation, police said, officers obtained video from the Safeway on Pine Street.

Three men are seen in the video with Avery and are being sought as witnesses to the incident.

The first person depicted in the video appears to be approximately 25 years old and wearing a distinct yellow shirt and black shorts with an upside down yellow "v" on each side.

The second person appears to be approximately 18 years old with curly brown hair and a distinct nose, police said.

The last person depicted appears to be in his 30s with brown hair and a moustache. He was wearing a grey hooded sweat shirt prior to being captured on video, police said.

Those with information about the identity of the three men are asked to call police at 225-4214 or Shasta County Secret Witness at 243-2319.

Avery was found naked and badly battered around 5:50 a.m..

He was discovered by a passerby at 5:50 a.m.

Police said the investigation reveals that Avery was violently bludgeoned with an object. He was taken by ambulance to Mercy Medical Center in Redding. A hospital spokeswoman said Avery is in serious condition there.